24 October 2008

Japanese lunar probe Kayuga (Selene) has tempered hope for large ice fields in the permanently shadowed crater floor of the Moon's polar regions as reported by New Scientist.

Shackelton Crater, one of NASA's targets for a future lunar outpost, was imaged by Kayuga using a camera specifically designed for low light uses. The floor of Shackelton Crater is in permanent shadow, making it impossible to photograph using normal techniques. Kayuga's Terrain Camera, a special stereographic imager, used scattered light to capture the floor of Shackleton Crater. During a short time frame in the lunar summer, sunlight scatters off of the rim of the crater and allowed Kayuga to directly image the floor of Shackleton. The results were telling in what was not found, rather than what was found.

The absence of clean water ice in the images is sure to discourage advocates of a return to the Moon. However, all the findings indicate is that there is no frozen lake of ice at the bottom of Shakleton. Ice may be buried under the regolith or even mixed into the hard, glassy lunar soil. Another possibility is that the hydrogen that Lunar Prospector detected is from another source. Frozen methane would be a boon to the outpost, giving astronauts access to both hydrogen a carbon which are both exceedingly rare on the Moon.